Rotationally locking a first set of brake discs to a planet carrier has been previously addressed such as in International Publication, WO 99/03699, for example. Therein, the brake discs are connected, via splines, on a radially outer surface of the planet carrier.
International Publication WO 04/18248 describes a planet transmission in which multiple planet wheel journals are connected to a common carrier for a brake disc. The brake disc is seated radially inside an axially projecting section of the common carrier. The brake is electrically controlled.